Answer: our government looks for ways to use OUR money to bail it out.
Carillion (formerly more plainly called Tarmac) owes £1.5 billion.
Why? Because it underbid for contracts and then racked up massive losses even when offering minimal services.
Why does it matter? Because it is a major contractor for the HS2 rail line and it also maintains 50,000 homes for the Ministry of Defence, manages nearly 900 schools, has NHS contracts and also manages highways and prisons and works with National Grid. It employs 43,000 people worldwide.
Imagine if Jeremy Corbyn had suggested it should be nationalised!